For consumers who have previously coloured their hair, the colour and condition of the hair is not homogenous along the entire length. The hair strands will comprise root virgin hair or new growth hair which has not been previously coloured and conversely at the tips hair which has experienced one or multiple hair colouring treatments. The tips of the hair typically are the most damaged portion of the hair and the colour will have changed over time dependant on the wash fade profile and number of types of hair colourant applied, amongst many relevant factors. The intermediate hair length is typically a medium between these two extreme conditions. As a consequence in the salon, for consumers who have previously coloured their hair, the salon stylists typically will colour the root virgin hair first with a specific composition to most effectively colour the hair to the desired end result. However, the remaining length of the hair and tips which has been previously coloured and may have undergone multiple colouring cycles is coloured with a separate and different composition to that applied at the roots. In this manner the salon stylist aims to provide a homogenous end colour result along the entire length of hair from root to tip independent of the variations of starting hair colour and condition along the hair length. Such method requires advanced professional skills in colouring hair for ensuring that the end result is satisfactory. Most consumers do not master such skills, and are unable to treat different strands and/or portions of hair with different hair colourant for achieving a satisfactory blend of tones.
The need for providing a retail hair treatment system, particularly a retail hair colouring and/or bleaching system, for use on roots and the entire hair length, has been met with the hair colouring methods, kits and compositions thereof disclosed in PCT patent application PCT/U.S.2013/027268, filed on 22 Feb. 2013. In such method, it is provided a first composition being a non-diluted hair colouring composition, and a dilutant component. A first portion of the first composition is applied onto hair, preferably onto hair roots, while the remaining second portion is mixed with the dilutant component for obtaining a diluted hair colouring composition, which is then applied onto hair, preferably onto hair lengths and tips. Alternative methods, compositions and kits have also been considered. For example, the first composition may be a hair perming composition and/or the second composition may a hair colouring and/or bleaching composition, a hair perming composition, a dilutant composition, a composition of lower pH than the first composition, a composition of higher pH than the first composition.
These methods, kits and compositions have proven useful for achieving a satisfactory hair treatment performance such as a superior hair colouring and/or bleaching performance, particularly for providing satisfactory root to tip treatment evenness. However, some consumers still struggle, after having applied the first portion of the first composition onto hair, in properly mixing the second portion with the second composition in the appropriate proportions and/or in a homogeneous fashion. Even when clear and detailed instructions have been provided, some consumers still find it difficult to obtain the mixed composition. Inappropriate and/or inhomogeneous mixing may provide, after application of the hair colouring composition onto hair, to unsatisfactory results such as differing and/or inhomogeneous tones, inappropriate blend of tone.
There is the need therefore for providing an improved method for treating hair being easy and intuitive to put into practise, even for the non-trained user. There is also the need for providing a method of treating hair for consumers having limited experience and/or skills in treating hair such hair colouring and/or bleaching hair.